Field of Invention
The present invention relates to the field of liquid crystal display technology, and more particularly to a GOA (Gate Driver on Array) circuit of a PMOS (P-channel Metal Oxide Semiconductor) based on LIPS (Low-Temperature Poly-Si), which is applied for a liquid crystal display device.
Description of Prior Art
GOA is a technology which utilizes the existing array process of TFT (Thin Film Transistor) liquid crystal display to manufacture the gate scanning signal circuits on the array substrates, so as to accomplish the cascade scanning on gate electrodes.
With the development of LTPS TFTs, due to the characteristic of extreme super-high carrier mobility of LTPS by itself, the relative integrated circuits around the panels, such as GOA, has become the focus concerned for the public. Many people are investing in the research of the corresponding technology of SOP (System On Panel), and thus the technology gradually becomes accomplished. LTPS can adjust the types of TFT by ion-coating technology to choose NMOS (N type Metal Oxide Semiconductor), PMOS (P type Metal Oxide Semiconductor), or CMOS (Complementary Metal Oxide Semiconductor) circuits. However, compared to PMOS, the mask costs are greatly increased in CMOS and NMOS. Also, the circuit structure of CMOS is too complicated to achieve an extreme narrow bezel design, and when focusing on display devices with smaller sizes, this will become much more important. Thus, PMOS circuits have become the mainstream due to the advantages of cost and circuit structure. Moreover, signal usage and power consumption are important issues in GOA circuits, which needs to be considered when designing LTPS circuits. Furthermore, since the scanning characteristic of small size products such as forward scanning and reverse scanning are more important than other characteristics, a GOA circuit based on LTPS PMOS is helpful to solve the above issues.